Ok so I just started programming in Java and I probably have the most infantile knowledge a person can have. How much of Java would I actually need to know before I could make a game using slick or some other engine? When I try I feel kinda stupid and lost when just the day before I understood or did something that made me feel like I hit a milestone.

If you want to be proficient, you need to understand logic. That's honestly more important than anything. Look at some syntax documents and API's and you can pick up any language. That is, if you understand the logic behind programming. At my job, I had to do web dev for a while. I had never touched PHP/Javascript and I was producing efficiently within 2 weeks (and that's mostly because I was trying to figure out where everything was in the 500+ files I worked in).

Then again, this is more a suggestion for people who want to program as a career. If you just want to try your hand at game programming, then you should at least have basic knowledge about the language you are using. If the only way you can make a "hello world" program is to copy a tutorial, then you aren't ready yet.

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